Nowadays, wearable electronic devices such as smart bracelets or sports wristbands are widely used. A process of producing the wearable electronic device will be described as follows. Firstly, plural electronic components are installed on a circuit board. Then, the circuit board with the electronic components is placed within a molding machine. In the molding machine, the circuit board is covered by a rubbery material, and the rubbery material is formed as a ring-shaped structure. Consequently, the smart bracelet or sports wristband with the ring-shaped appearance is fabricated. Due to the ring-shaped appearance, the mart bracelet or sports wristband can be worn on the user's hand.
After the forming process is completed, the circuit board of the conventional smart bracelet, the conventional sports wristband or any comparable wearable electronic device is sealed within the rubbery material. Consequently, the circuit board of the produced wearable electronic device cannot be removed. Moreover, since all of the electronic components are installed on the circuit board after the forming process is completed, the electronic components cannot be replaced. Moreover, after the forming process is completed, the circuit board cannot be connected with another circuit board. Since the wearable electronic device cannot be equipped with an additional circuit board, the functions of the wearable electronic device cannot be expanded. In other words, it is difficult to replace and maintain the electronic components of the wearable electronic device, and the functions of the wearable electronic device are limited. Therefore, there is a need of providing an improved wearable electronic device in order to overcome the above drawbacks.